* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 400px;
}

.login-form {
    background: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 30px;
    font-size: 28px;
    font-weight: 600;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
    font-size: 14px;
}

input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 16px;
    transition: all 0.3s ease;
}

input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

input.error {
    border-color: #e74c3c;
}

.error-message {
    display: block;
    color: #e74c3c;
    font-size: 12px;
    margin-top: 5px;
    min-height: 15px;
}

.login-btn {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 10px;
}

.login-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.login-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.message {
    margin-top: 15px;
    padding: 10px;
    border-radius: 6px;
    text-align: center;
    font-size: 14px;
    display: none;
}

.message.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.loading-spinner {
    display: inline-block;
}

/* 响应式设计 */
@media (max-width: 480px) {
    .login-form {
        padding: 30px 20px;
        margin: 10px;
    }
    
    h1 {
        font-size: 24px;
    }
    
    input {
        font-size: 16px;
    }
}

@media (max-width: 320px) {
    .login-form {
        padding: 20px 15px;
    }
}
